Full bore directional drilling tool



Nov. 11, 1969 A. R. MARKS, JR

FULL BORE DIRECTIONAL DRILLING TOOL 3 Sheets-Sheet 1 /4/`fea/ f?. Mavvv/cr, JF'.

INVENTOR.

mmm

Filed Feb. 6, 1968 Nov. 11, 1969 A. R. MARKS, JR

FULL BORE DIRECTIONAL DRILLING TOOL 5 Sheets-Sheet 2 Filed Feb. 6, 1968 u n1 I IlfllL. 4 :in u lei INVENTOR.

3 Sheets-Sheet 5 /f/'ec/ A? Mar/5J, e/

INVENTOR.

A. R. MARKS, JR

FULL BoRE DIRECTIONAL DR-ILLIN TooL Nrw. 11, 1969 Filed Feb; e, 196e United States Patent O 3,477,524 FULL BORE DIRECTIONAL DRILLING TOOL Alfred R. Marks, Jr., 1006 N. Travis St., Liberty, Tex. 77575 Filed Feb. 6, 1968, Ser. No. 703,476 Int. Cl. E21b 7/04, 7/06 U.S. Cl. 175-82 14 Claims ABSTRACT OF THE DISCLOSURE This directional drilling tool consists of a casing having an internal deilecting face `and `a mandrel extending entirely through the casing and biased toward the deecting face. The mandrel may be latched to the casing for running the tool and its full bore bit into the well and drilling out obstructions on the way, `and the latch is disengaged and one or more stabilizing lugs actuated to permit rotation and advancement of the mandrel within the casing.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to tools for drilling deflected bore holes in the ground and consists particularly in a novel tool which eliminates a number of steps heretofore necessary with the use of conventional whipstocks for the same general purpose.

Description of the prior art Where it is desired to deflect a bore hole, either to divert it from vertical or to return it to an intended position, it has been customary to run into the 'well at the end of the drill pipe string a whipstock which consists of a body having a longitudinal delecting face against which a small drill bit rides, The bit is advanced along the dellecting face and then into the bottom of the bore hole at the established angle which is maintained by drill collars or other relatively stit structure rearwardly of the' bit. It is necessary, then, to ream out the deected hole before normal drilling can be resumed, or in case the detlecting operation is to be repeated to increase the hole deviation. In such case, it is necessary to completely withdraw the drill string and whipstock from the hole and run 'a hole opener bit into the hole, since the whipstock itself cannot drill as it is being run in. The deflection bit is then relatched at the top of the dellection face of the whipstock body and rerun with the whipstock into the bottom of the well.

SUMMARY OF THE INVENTION The tool, according to the present invention, consists of an elongated, hollow casing having a longitudinal deecting face in the lower portion thereof and through which a mandrel extends. The upper portion of the mandrel projects beyond the top of the casing and is adapted for connection of the supporting drill pipe string. The lower part of the mandrel projects beneath the bottom of the casing and mounts a full-bore drill bit, conveniently of the tricone or other rotary type. The mandrel is flexible, either inherently or by virtue of a universal joint interposed medially therein, and is biased toward the deflecting face of the casing by a kick protrusion on the internal casing wall opposite the dellection face. A lug on the upper portion of the mandrel is received in a longitudinal slot in the casing inner wall whereby the casing and deflection face may be oriented from the surface in any conventional manner by manipulation of the drill string. A shear pin connects the mandrel upper part to the casing during running into the well when it may be necessary to use the deection tool to drill out obstruc- "ice tions in the bore hole while retaining the casing and mandrel rigidly connected together. A telescoping joint interposed in the mandrel may be collapsed, when the tool is at the bottom of the hole, or breaking the shear pin and 'withdrawing the mentioned mandrel lug from the casing slot to permit rotation and advancement of the drill bit within the casing for drilling a deecte'd hole the lower end of the casing, In case additional deviation is required, it is simply necessary to lift the drill string so as to fully expand the mentioned telescoping joint Iand then retract the mandrel into the casing. Latching elements are provided between the mandrel and casing which may be re-engaged in the fully retracted position of the mandrel, to permit running of the now connected casing and mandrel further into the well. A spiral shoulder of the mule shoe type at the lower end of the casing slot directs the mandrel lug into this slot for orientation of the casing and deflecting face. When the tool is thus ready for repeated action, downward pressure on the drill string breaksl the re-engageable latch and removes the lug from the slot for resumed rotation and advancement of the mandrel and drill bit.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings which illustrate the invention,

FIG. 1 is an elevation of the novel deflecting tool run in a well and with the casing shown in longitudinal section.

FIG. 12 is an enlarged view of the upper part of the deilector structure in FIG. 1.

FIG. 3 is a horizontal transverse section taken substantially in line 3 3 of FIG. 2.

FIG. 4 is an enlarged horizontal transverse section taken on line 4 4 of FIG. l.

FIGS. 5, 6, 7, and 8 are views similar to FIG. 1, but showing the tool in different stages of operation.

FIG. 9 is an enlarged detail longitudinal section taken substantially on line 9 9 of FIG. 2.

FIG. l0 is an operation-al view similar to FIGS. 1, 5, 6, 7, and 8, but showing a modification.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the novel fullbore dellection tool suspended in a well bore 12 by means of a string of drill pipe 13 provided with a pin coupling joint 14 at its lower extremity for connection to the box coupling joint 15 at the upper extremity of an upper mandrel portion 16 of the tool. The mandrel also includes a reduced part 17, rigid with upper portion 16, and having at its lower extremity a spline 'forming head 18 which is slidably received in splineways 19 in an elongated cylinder 20. Elements 17 and 20 form a telescoping joint interposed medially within the mandrel. Cylinder 20 at its lower end is secured to a universal joint 21 which, at its lower end, is secured to a mandrel lower portion 22 which may be made up of one or more drill collars. At the extreme lower end of the mandrel, there is provided a rolling cone type drill bit 23.

A casing, generally designated 26, encompasses the mandrel 16, 20, 21, 22, which, as shown ,extends entirely through the casing. Along the inner wall of the lower portion of the casing there is provided a deflecting face 27 which is inclined to the axis of the casing and also of bore hole 12 at the desired angle of hole deviation. Pivotally mounted in a slot 28 in the upper part of the casing is a stabilizer detent having a short, inwardly projecting finger 29 (FIGS. 1 and 2) and a longer, normally depending linger 30 with a point 31 at its extremity. A shoulder 32 at the intersection of mandrel portions 17 and 16 is positioned to engage detent linger 29, as will be explained. Mounted on upper portion 16 of the mandrel is an annularly resilient split ring 33, shown in detail in FIG. 9 as received within an annular groove 34 in mandrel portion 16. In the latched position of the mandrel, as shown in FIGS. 1, 2, 6,- 7, and 9, ring 33 expands into a groove 35 in the inner wall of casing 26 to latch the mandrel against longitudinal movement relative to the casing. The ring and groove have abutting inclined wedging surfaces 36 and 37. FIGS. 1 and 2 also show casing 26 rigidly secured to mandrel portion 16 by means of a shear pin 38. A longitudinal groove 39 in the upper part of the casing slidably receives a radial lug 4t) on mandrel portion 16, in the latched position of FIGS. 1, 2, 6, and 7, to additionally lock the mandrel against rotation within the casing. Groove 39 terminates at its lower extremity in a spirally curved shoulder 41 (mule shoe) which will direct lug 40 into groove 39 when the mandrel is lifted through the casing. Projecting from the inner wall of the casing is a kick lug 42 which bears :against the mandrel for biasing the same toward deflection face 27.

The modification in FIG. l() may be like that in the iirst form in all respects, except for the elimination of universal joint 21. In this form, the flexibility of the mandrel is achieved by a long section of tubing 45 which extends beneath the bottom end of casing 26 and mounts a drill bit, las at 23 in the previous form. The amount of weight applied to mandrel upper portion 16 through the drill string determines the amount of llexing of lower mandrel portion 45 and, consequently, the degree of deviation of the hole drilled. Increased weight applied to the drill string will increase the bend at 45 and, therefore, the deviation of the hole.

The new tool operates as follows: FIGS. 1 and 2 show the tool run into a well on la drill string 13 with telescoping joint parts 17 and 20 fully expanded and upper mandrel portion 16 secured to the casing by shear pin 3S. Drill bit 23 rests upon the bottom of the hole 12 previously drilled, and the tool is oriented from the surface by any suitable orienting mechanism acting through the drill string. Weight is then applied to the drill string for shearing pin 38 and forcing latch ring 33 out of groove 35 in the casing, this being effected by means of camming surfaces 36 and 37, respectively, on ring 33 and the groove, when downward pressure is applied to the ring, causing the ring to contract and withdraw from groove 35. Mandrel portion 16 is then lowered, relative to the casing, causing complete contraction of telescoping joint parts 17 and 20 and withdrawal of lug 40 from casing groove 39. Also, shoulder 32 engages and rotates finger 29 causing outward swinging of the stabilizing lug or lugs and biting thereof into the bore wall. Drilling weight and rotation are then applied through the drill string to the mandrel and drill bit, the mandrel new being free to rotate and advance through the casing. Also, suficient weight is applied to the mandrel to cause its lower portion 22 to rest against the inner wall of casing 26 above dellection face 27. FIG. shows lower mandrel portion 22 substantially fully ejected beyond the casing and into the dellected bore hole portion 12a drilled by bit 23. Between the positions of FIGS. 1 and 5, mandrel portion 22 has reached llush abutting relationship with dellecting face 27, after which bit 23 drills straight. The rst part of the deflected hole, before the top end of mandrel portion 22 arrives at face 27, is slightly curved. Importantly, deflection face 27 is provided with cord-like side faces 27a and 27b which form a trough for receiving and laterally engaging the mandrel to prevent lateral deviation thereof-that is, deviation normal to the plane of the desired deviation.

Now to continue the drilling with the novel detlection tool, the drill string and upper mandrel portion 16 are elevated (FIG. 6), first expanding telescoping joint parts 17 and 20 to cause latching ring 33 to again enter casing groove 35 and lug 39 to re-enter groove 40, being guided I 4 n thereinto by spiral shoulder 41. In the process, stabilizing detent 30 will `be rotated to its inoperative position, as in FIGS. 1 and 2. Mandrel lower part 22 will then be substantially fully located within the casing with only its lower extremity and bit 23 projecting therebelow. The entire tool may now be reoriented and then advanced to the bottom of newly drilled deviated hole portion 12a, as shown in FIG. 7. Weight will be applied to mandrel portion 16 to unlatch ring 33, to contract telescoping parts 17 and 20, and swing stabilizing lug 29, 30 outwardly to its bore wall engaging position. However, if the weight applied to the drill string is insullcient to unlatch ring 33, the hole will be continued in line with portion 12a. If the drill string is again weighted sulllciently to disengage latch ring 33 and to cause lower mandrel portion 22 to rest against and ride along diverting face 27, a further deviation of the hole in the plane of the previous deviation will result. This process may be repeated until the required hole deviation is achieved, the repeated steps, including correction of tool orientation, being effected simply by returning the mandrel to its FIG. 1 position within the casing, correcting orientation, advancing the entire tool to the bottom of the hole, and repeating the unlatching, stabilizing, and drilling steps. It will not be necessary to return the tool to the surface for hole opening and bit resetting operations, as has been necessary where a conventional whipstock hole diverter is used. Shear pin 38 is provided for initial running of the tool into the well when it may be necessary to use the full hole bit to clean out bridges and other obstructions in the hole, a function which, of course, cannot be performed by conventional whipstocks in which the bit in its retracted position rests upon the deflection face of the tool. Also, the tool, in the latched positions of FIG. 6, may, likewise, be used for straight hole drilling or cleaning out bridges or other obstructions in the hole, irrespective ofthe shear pin.

Accordingly, with the use of the novel tool, as many as four or five round trips will be avoided, for instance, in the drilling of 200 feet of diverted hole, and, of course, no special hole-opener bit or step is required for cleaning out and enlarging the hole, the full gauge bit attached to the tool and the pressured drilling fluid being suilcient for this purpose. Thus, hours of time are saved in hole diverting operations. The second form shown in FIG. 10 has the further advantage of permitting some variation of the deviation angle under the control of the weight applied to the drill string. The invention may be modified in various respects as willoccur to those skilled in the art, andthe exclusive use of all modications as come Within the scope of the appended claims is contemplated.

I claim:

1. A deflection drilling tool comprising an elongated casing, a dellection face extending along the inner wall of said casing at an angle to the axis thereof, a ilexible mandrel extending through said casing and normally protruding beyond the ends thereof, full hole drill bit means at one end of said mandrel, and drill string connection means at the other end thereof for applying axial drilling forces to said mandrel to cause said mandrel to llex and slide along said face and thereby divert the hole being drilled relative to said casing axis.

2. A deflection tool as described in claim 1 in which said deflection face forms a trough which laterally abuts said mandrel in the face engaging position thereof to resist lateral deviation of said drill bit means.

3. A dell'ection drilling tool as described in claim 1 further including a universal joint medially inserted in said mandrel to form mutually deflectable forward and rearward portions, said mandrel forward portion being located abreast of said dellccting face in said casing for guidance thereby.

4. A deflection drilling tool as described in claim 1 further including abutment means on the confronting walls of said casing and said mandrel for biasing said mandrel toward said deflection face to insure guidance of said mandrel and the bit by said deflection face during dellection drilling by the tool.

5. A deection drilling tool as described in claim 1 in which said drill bit means includes a full hole bit having gauge structure at least slightly greater in O.D. than the O.D. of said casing.

6. A dellection drilling tool as described in claim 1 further including latching means between said mandrel and said casing, said latching means being disengageable permit longitudinal movement of said mandrel along said deflection face for deviated drilling and being re-engageable for running the tool into a well and drilling with said mandrel and casing latched together.

7. A deection drilling tool as described in claim 1 further including bore wall gripping means carried by said casing and means on said mandrel for causing said gripping means to engage the bore wall to stabilize said casing relative thereto for control of the hole deviation produced by the tool.

8. A deflection drilling tool |as described in claim 1 further including a lug device movable carried by said casing and an element on said mandrel for actuating said device outwardly into engagement with the bore wall upon shifting of at least 1a portion of said mandrel relative to said casing to stabilize said casing and thereby control the deviation of the hole being drilled.

9. A deilection drilling tool as described in claim 1 further including bore wall gripping means carried by said casing and means on said mandrel for causing said gripping means to engage the bore wall to stabilize said casing relative thereto for control of the hole deviation produced by the tool, said mandrel including telescoping parts, one of which is disposed to shift said gripping means outwardly into stabilizing engagement with the bore wall during telescoping of said parts.

10. A deflection drilling tool las described in claim 1 further including interengageable elements on said casing and said mandrel for causing joint rotation of said casing and said mandrel, said elements being disengageable upon `advance of said mandrel through said casing to permit rotation of said mandrel within said casing.

11. A deflection drilling tool as described in claim in which said mandrel includes rearward and forward telescoping parts, said rearward -part including one of said interengageable elements whereby said elements may be disengaged by manipulation of said rearward part independently of said forward part.

12. A deection drilling tool as described in claim 11 further including means for detachably securing said rearward part to said casing and means preventing longitudinal disengagement of said telescoping parts whereby said tool may be supported by said drill string connectiori for running into a well.

113. A dellection drilling tool as described in claim 12 in which said securing means comprises operatively reengageable latch means whereby said rearward telescoping part may be again secured to said casing for further runping of the casing and mandrel into the Well to contine drilling thereof after formation of =a deflected portion. of the bore hole.

14. A deflection drilling tool comprising a casing, an internal deflection face extending along the casing at an angle to the axis thereof, a flexible mandrel extending thrugh said casing with =a rearwardly projecting -portion for attachment of drill pipe and a forwardly projecting portion for mounting a drill bit, abutment means in said casing for biasing said mandrel toward said dellection face, a telescoping joint interposed medially in said mandr'l including upper and lower telescoping parts, cooperating orientation guide means on said casing and said mandrel for orientation of said casing and said deflection face by manipulation of said drilling string connection, disconnectable latch means on said casing and said mandrel rearwardly of said telescoping joint for joint sup. port of said casing and said mandrel by said drill string connection and disengageable and re-engageable to permit selective advancement of said mandrel through said casing` in deflection drilling and retraction of said mandrelfto latched position within said casing for running the tool further into the well being drilled and for drilling of the hole while in latched position.

References Cited UNITED STATES PATENTS 2,716,542 8/1955 Goble 175-82 X 2,823,012 2/1958 Hanna 166-1 17.5 X 2,882,015 4/1959 Beck 166-117.6 X 3,339,636 9/1967 Frisby 175-82 X NILE C. BYERS, JR., Primary Examiner U.S. Cl. X.R. 

